With the cell phone technology, the mobile phone battery was a “regime change”. In the first NiCd and NiMH Li-ion battery, and then Li-ion polymer batteries. Greater energy density, smaller size, greater life expectancy of mobile phone batteries strong support for the development of mobile phone. The mobile phone battery following are the key technologies and important parameters to make a brief review. IBM ThinkPad R52 battery IBM ThinkPad T40 battery
Batteries mobile phone technology
The battery technology application to a large extent by decisions based electric technology development. With the continuous development of technology, batteries, NiCd and NiMH batteries gradually decreased at the same time, Li-ion battery production has risen steadily, and the Li-ion polymer batteries have started to occupy a certain market share.
In general, batteries have two electrodes anode and cathode. Anode to release electrons and produce a lot of holes, the polarity is positive accumulation of cathode electronics, the polarity is negative. Pricing, the current in-house flow of the anode cathode discharge to the contrary, the current outside the cathode to the anode, the power load. Parameters common battery performance are defined as follows: If a battery is fully charged after the discharge capacity after an hour the whole space, then the current rate of 1C; to recharge a battery or batteries pieces full of tension ( 4.2 V for example), then through the discharge power is empty (eg, 3.0 V) is called a charge-discharge cycles, when the battery capacity to maintain a valid value (like amount of charge up to 80%), the battery charge and discharge cycles can increase the number of known life cycle of the battery. Dell Inspiron 1300 battery Dell Inspiron 1420 battery
1. NiCd and NiMH batteries
NiCd batteries use cadmium as the anode, the cathode NiOOH. NiCd batteries have a life cycle longer, better temperature characteristics and high density of the battery. As a battery faster, Cd pollution material is relatively heavy environmental and density of the battery must be further enhanced, while NiCd battery is difficult to increase the capacity and will be disposed of market applications.
NiMH batteries using MH as the anode, cathode and NiOOH. NiMH battery is charged and the discharge characteristics, and cell density than nickel-cadmium batteries has increased by 30%, and are more environmentally friendly. NiMH better safety performance in itself, it was anti-overload protection and self-discharge capacity of healing, compared to Li-ion batteries, it does not require additional protection circuit and board containing PCBs. NiMH batteries have many advantages, but in the charging efficiency, battery and the density of leakage current of these areas need further improvement. 338794-001 361742-001
2. Li-ion batteries
Li-ion batteries using carbon or graphite as the anode and the metal oxides or Co / Ni / Mn cathode, organic, or an electrolyte solution to polypropylene as insulation. As the material, Li-Ion batteries must be placed under some form of cans solid, if pressure is good, and the shape is fixed.
Li-ion batteries provide 3.6V operating voltage is generally more stable performance. Its power density is very high self-discharge of the leakage current is small, large capacity and a small external. In addition, Li-ion batteries, long battery life, typically more than 400 cycles of loading and unloading, and the life cycle of work and stable performance. Figure 1 show the different life cycle of the Li-ion battery under the 1C discharge voltage and the curve of time. VGP-BPS5 VGP-BPS9A
When the Li-ion batteries in cell controlled by the field of traditional chemistry, in improving the energy density at the same time, the design of the battery and the chemical change also makes the key parameters of the battery can be improved. Li-ion battery has been applied in many system designs, it may be well positioned to meet the energy needs of the system.
Of course, Li-ion batteries is volatile and flammable material composition, and therefore the design of the battery, safety is an important criterion.
3. Li-ion polymer battery cells
Li-ion polymer batteries batteries batteries with Li-ion battery similar to the use of carbon as the anode, metal oxides as cathode, gel electrolyte membrane using the gel as an insulator. Li-ion polymer batteries have greater capacity and higher energy density. With the Li-ion batteries similar to its self-discharge of the leakage current is low. However, Li-ion polymer battery of stability is not good, so it needs to operate more stringent. A1060 M8403
Li-ion polymer battery technology to significantly improve the energy density of battery life, temperature and duration of conservation, energy efficiency of the battery is very high. Appearance, Li-ion polymer batteries using plastic containers, compared to Li-ion battery shell metal has a definite advantage, but the Li-ion polymer batteries are also easy to force expansion, so the production of materials, flexibility of error for a strict control. From a security standpoint, Li-ion polymer batteries and battery fever electrolyte leakage problem has been a real headache. Because Li-ion polymer battery is easy to develop, its reliability needs further improvement.
In short, there are many manufacturers in the continually improving Li polymer battery technology, and supply-ion batteries with the same service prices. However, the stability of the polymer has not been verified, but also be further improved and developed.